1. Field of the Invention
This invention relates, in general, to transmissions, and, more specifically, to transmissions having a plurality of selectable forward and reverse modes of operation.
2. Description of the Prior Art
The modern automobile is undergoing a dramatic change in design due to government regulations relating to safety and emission standards and, also, due to the ever increasing cost of fuel. All of these factors have resulted in the development of smaller, lighter vehicles which necessarily have smaller and less powerful engines.
Due to the low horsepower provided by these smaller engines, transmissions are required which provide a wide range of gear ratios in order to maintain satisfactory drivability over a wide range of driving conditions and, also, high fuel economy. A narrow range of engines RPM's is also essential in order to maintain the desired emission levels. This again illustrates the need for a transmission having a wide range of gear ratios.
While it is known to construct vehicle transmissions having multiple gear ratios, such transmissions have a long overall length which, while acceptable for use in larger vehicles, cannot be adapted for use in smaller vehicles due to space constraints. The space constraints placed in vehicle transmission design is further aggravated in front wheel drive type vehicles having transverse mounted engines. In such a vehicle configuration, the engine, transmission and drive train are located entirely between the front wheels of the vehicle which, in small vehicles, is an extremely limited space. This narrow space has prevented the use of previously devised transmissions having the desired number of gear ratios for satisfactory driving under all conditions, maximum fuel economy and low emissions.
Similiar space constraints and/or the need for a large number of selectable gear ratios are also encountered in other types of motive power apparatus, such as lathes and other machine tools, farm vehicle, fluid mixers, etc.
Thus, it would be desirable to provide a transmission for a vehicle which overcomes the problems of previously devised transmissions. It would also be desirable to provide a transmission which includes a wide range of selectable gear ratios. It would also be desirable to provide a transmission which provides a wide range of gear ratios in a small, compact space. It would also be desirable to provide a transmission which can be constructed in a variety of different configurations for use in a large number of applications and vehicle and engine configurations. Finally, it would be desirable to provide a transmission which is particularly suited for use in transverse mounted, front wheel drive vehicles.